Most people who make their own fermented foods — preserved products such as sauerkraut that contain live bacteria — fall into it by accident.
But as they start to do more research, they discover an amazing world of ancient foodstuffs boasting all kinds of extra benefits, from complex flavors to improved digestion and health.
"By eating fermented foods, we increase the biodiversity of the flora in our intestines," said Jeff Cox of Kenwood, author of the new book "The Essential Book of Fermentation." "When you have a constant flood of good guys, the bad guys can't get a hold."
Jennifer Harris, who organized the Farm to Fermentation Festival last weekend in Santa Rosa, said it's an exciting time to be sharing her fascination with fermented foods with others.
"People are slowly getting more comfortable with it," she said. "And they're starting to think of bacteria as sexy, like a glass of red wine."
While the popular kombucha (fermented tea drink) can be found across the country, The Shed in Healdsburg may be the first in the nation to offer a "fermentation bar," showcasing kombuchas and hard ciders as well as tasty "shrubs" — drinks made with sweet-sour vinegar syrups.
"I think we're a little ahead of the curve here in Sonoma County," said Mary Karlin of Petaluma, whose latest cookbook, "Mastering Fermentation," is due out Tuesday. "Wild yeasted bread has been going for 15 years or so. Then cheese became the new bread, and now kimchi (Korean sauerkraut) is the new cheese."
Karlin, who teaches cooking classes all over the Bay Area, starts her students off with some of the more popular and accessible fermented foods.
"At The Fork in Point Reyes, we do fermented dairy," she said of the farmstead center in West Marin. "So we do cultured butter; creme fraiche, which is easy; cream cheese; and dairy kefir (a yogurt-like, fermented-milk drink).
Like many health seekers, Karlin has made the sour, effervescent kombucha part of her daily routine.
"It's one of those things I cannot live without now," she said. "I drink a little bit in the morning, and a little bit throughout the day."
Karlin suggests making pickles or shrubs if you are new to the culture club.
"I'm crazy about the shrubs," she said. "Because they are made with vinegar, people find them standoffish. But you have to taste it to understand."
One of her favorite shrubs combines the refreshing flavors of ginger and mint. She makes it with raw apple-cider vinegar, but any raw vinegar (with live bacteria) will work.
"You macerate the very ripe fruit in the vinegar," she said. "I leave it out for 12 hours. ... It's more fizzy."
Cox's curiosity about fermented foods was first piqued by his interest in organic gardening. (He was an editor at Organic Gardening magazine in the 1970s and now writes restaurant reviews for The Press Democrat.)
After hearing Cox give a talk in the 1980s comparing plant-root hairs with the hair-like villi of the human intestine, author Wendell Berry suggested he write a book.
Decades later, Cox has finally published that book, which explains the science behind fermentation; delves into the worlds of bread, cheese and wine; and provides recipes for do-it-yourselfers.
As part of his daily routine, Cox drinks a tangy, dairy kefir he makes from a "SCOBY," which stands for "symbiotic combination of bacteria and yeast."